Process of preparing artificial textile products with reduced luster



Patented Dec. 9, 1930 UNITED STATES PATENT OFFICE THEODOOR KOCH, OFARNHEM, NETHERLANDS, ASSIGNOR TO ALGEMEENE KUNSTZIJDE UNIE NAAMLOOZEVENNOOTSCHAP, OF ARNHEM, NETHERLANDS PROCESS OF PREPARING ARTIFICIALTEXTILE PRODUCT WITH REDUCED LUSTER No Drawing. Application filedOctober 3, 1927, Serial No. 223,833, and in the Netherlands April 7,1927.

In my patent application Ser. No. 223,831, filed Oct. 3, 1927, I havedescribed a process for preparing artificial textile products withreduced luster, from viscose, according to which chlorobenzene or amixture of monoand di-chlorobenzene is added to theviscose. According tomy invention the said substances are added preferably in suchproportions that the specific weight of the additions practicallycorresponds with that of th viscose to be worked up.

According to my above mentioned process an artificial silk of very goodproperties, with reduced luster, is indeed obtained. In practice,however, diificulties are encountered and especially if artificialthreads below six denier are to be prepared according to the processdescribed in the above patent.

After laborious researches it appeared that the cause of these lessfavourable results must be seen in the insufficient division of theadditions, and that the large number of spinning faults occurring duringthe spinning of fine denier silk must be ascribed thereto. According tomy invention it is possible to prepare silk with reduced luster and alow denier number per elemental fibre with the aid of my above mentionedprocess.

Further it has appeared that a special proportion exists between thelargest allowable diameter of the particles and the denier number perelemental fibre of the silk to be spun.

According to my invention the dimension of the particles of theadditions is preferably chosen smaller as finer threads are to be spun,and this in agreement with the equation 40 in which D is the deniernumber of theelemental thread, a the largest allowable dlamieter inmicrons of the parts, and c the constant, which for normal viscoseamounts to about the dimension of the parts for 0=% is given by thefollowing table allowable diameter of the additions is 6.9. From theequation D 0 (a a) it follows that a fromwhiclrit follows that c= I r Inthis way the constant c'may be'determined forany viscose, which, as hasalready been observed,is about Afor a normal spinning viscose. v

If it is desired to determine for a Viscose, so

of which the constant is c, the largest allowablediameter of theadditions for a different denier per elemental fibre, one proceeds asfollows If a denier of 3 is to be spun, the equation 1s D c(a +a) =9=%(a+a), from which it follows that After it was found that in general for alow denier number the diameter of the added particles should be smaller,it was not to be foreseen that the'largest permissible diameter of theparticles would have aspecial function depending upon the fineness ofthe silk, and that the denier number would be a double function of thediameter.

It is clear that one is enabled by this rule to pie-determine for anydesired fineness of the silk which has the largest allowable diameter ofthe added oarticles; so that by applying the process according to myinvention, it is possible to spin very fine .deniers and to obtain aproduct of reduced luster.

It is obvious that the usual measures for spinning low denier silk havealso a. favourable influence in the process according to my invention.Also, as can be expected, the well-known favourable influence of a smallamount of zinc sulphate in the spinning bath is perceptible in thisprocess.

I claim:

1. In a process of preparing a solution of viscose containingchlorobenzene for spinning into artificial silk threads with a reducedluster and of a size below 6 denier, the step of emulsifying thesolution to such an extent as to form particles of chlorobenzone of adiameter which is a function of the denier number of the threads whichare to be spun, which diameter varies according to the formula :D =c(aa), in which D the denier number, a the largest allowable diameter ofthe particles in microns, and c a corn stant, which for normal viscoseis about twothirds.

2. In a process of preparing a solution of viscose containing a mixtureof mono and di-chlorobenzene for spinning into artificial silk threadswith a reduced luster and of a size below 6 denier, the step ofemulsifying the solution to such an extent as to form particles ofmonoand di-chlorobenzene of a diameter which is a function of the deniernumber of the threads which are to be spun, which diameter variesaccording to the formula :D=c(a +a), in which I) is the denier number, athe largest allowable diameter of the particles in microns, and 0 aconstant, which for normal viscose is about twothirds.

3. In a process of preparing a solution of viscose containing a mixtureof monoand dichlorobenzene for spinning into artificial silk threadswith a reduced luster and of a size below 6 denier, the relativeproportions of which mixture are such that the specific weight of themixture of monoand dichlorobenzene practically corresponds with that ofthe viscose, the step of emulsifying the solution to such an extent asto form particles of monoand di-chlorobenzene of a diameter which is afunction of the denier number of the threads which are to be spun, whichdiameter varies according to the formula :D 0(a +a), in which D is thedenier number, a the largest allowable diameter of the particles inmicrons, and c a constant which for normal viscose is about twothirds.

4. In a process of preparing a solution of viscose containingapproximately 1% oil a mixture of monoand di-chlorobenzene for spinninginto artificial silk threads with a reduced luster and of a size below 6denier, the relative proportions of which mixture are such that :thespecific weight of the mixture of monoand di-chlorobenzene practicallycorresponds with that of the viscose, the step of emulsifying thesolution to such an extent as to form particles of monoanddi-chlorobenzene o-f:a diameter which is a function of the denier numberof the threads which are to be spun, which diameter varies according tothe formula :D =c(a +0), in which I) is the denier number, a the largestallowable diameter of the particles in microns, and c a constant, whichfor normal viscose is about two-thirds.

In testimony whereof I affix my signature.

THEODOOR KOCH.

